Improvement in cranks for saw-mills



A. Rennens'. Cranksl for Saw-Mills.-

Patented September 16., 1873.

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UNITED STATES PATENT OEEICEl ALEXANDER RODGERS, OF MUSKEGON, MICHIGAN.

IMPROVEMENT IN CRANKS FOR SAW-MILLS.

fipecication forming part of Letters Patent No. 142,816, dated September 16, 1873 application filed August 30, 1873.

To all whom it may concern:

Be it known that I, ALEXANDER RoDGERs, of Muskegon, in the county of Muskegon and State of Michigan, have invented certain new and useful Improvements in Granks for Saw- Mills; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawings, which form part of this specilication.

This invention has for its object to furnish a strong and reliable crank, as Well as to provide a speedy means for adjusting the crankbalance to the ever-varying weight of the gates in gang-saw mills; and it consists inthe construction and arrangement ot' the diereut parts of the device, as will be hereinafter more fully set forth. l

In the accompanying drawings similar letters of reference indicate like parts in all the figures.

Figure l is a vertical cross-section of a sawmill, and shows the position occupied by my improved crank. Fig. 2 is a side view ot' the crank, and shows the method of securing the balance-weight upon it, also, one endet' the shaft to which it is attached. Fig. 3 is a longitudinal section of Fig. 2. Fig. et presents an end view of the crank with a portion of its shaft attached.

A is the crank-body, formed preferably of wrought-iron or steel, and is of the form in common use, which experience teaches us 'at'- `fords a proper distribution ot the material to give equal and proportionate strength to all its parts. It is provided with an lorifice at one end to receive the erank-pin B, and auother central opening, through which passes the shaft C, to which it is secured by the key a. From the end opposite the crank-pin projects a rectangular shank, D, which I prefer to have forged from the same piece of metal as the body of the crank, in order to secure the greatest amount of strength possible. A slot, c, is formed in this shank, through which passes the bolt d, a counter-balance, E, of castiron, forming nearly the segment of a circle, and haviuga radial recess formed for the reception of the shank D, and to which it is adjustably secured by the bolt b and a key, K. This key is provided with a slotted keeper, m, which is secured to the counter-balance by a set-screw, a.

It will be seen that this method of adjustment enables the sawyer, when the weightot the gate has been changed by the removal of', or addition to, the number of saws, or by any other means, to readily adjust the counter-balance to its weigl1t,and it therefore enables him to keep the working parts so nicely balanced as to avoid the jar and tremor so injurious to the building as Well as machinery of the mill, and disagreeable to the persons who, while working in the mill, arc of necessity exposed to its action.

It will also be apparent that, although I have described my improved crank as applied to a saw-mill, its use is by no means limited thereto, as it is equally as well suited to the engines ot' propellers, and in fact nearly all positions where a balance-crank is required.

Having thus described my invention, I

claim as new and desire to secure by Letters Patentl. A balance-crank constructed as herein described, and for the purpose set forth.

2. The counter-balance E and key K, provided with the keeper m, in combination with the crank-body A, shank D, and bolt b, substantially as and for the purpose specified.

In testimony that I claim the foregoing I have hereunto set my hand this 18th day otl August, 1873.

ALEXANDER RODGERS.

Witnesses:

FERDINAND WOTTENBERG, l J AMEs O. MCLAUGHLIN. 

